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Cetaceans (Order Cetacea) (whales,
dolphins and porpoises)
1. Odontocetes (Suborder Odontoceti)
Toothed cetaceans with one blowhole. (The odontocetes include
all porpoises and dolphins, and a few true whales.)
1a. Porpoises (Family Phocoenidae)
-Dall's Porpoise (Phocoenoides dalli)
phocoena=porpoise oides=like William Dall= a zoologist
Size: Up to 2 meters. Newborns are typically 1 meter long.
Color: Black with white patches.
Group size: 2-15 individuals.
Diet: Squid and small schooling fish.
Description: Dall's porpoises are the fastest cetaceans, traveling
at a top speed of 30 knots. They are also the most common
cetacean in local waters, and are found throughout the temperate
waters of the North Pacific. When Dall's porpoises swim rapidly
at the water's surface (porpoising) they throw a characteristic
rooster-tail spray that is obvious from quite a distance.
They will occasionally ride in the bow wave of boats. When
feeding they swim in circles and slowly roll at the surface,
arching their backs steeply just before a deep dive. This
"arching" or "sounding" behavior emphasizes
the steep bend in the Dall's porpoises caudal peduncle, leading
the native Washingtonians (the Quillayutes and the Makahs)
to name it "broken tail." Notice that the leading
edge of the dorsal fin is shorter and steeper than the trailing
edge.
-Harbor Porpoise (Phocoena phocoena)
phocoena=porpoise
Size: Up to 1.8 meters.
Newborns are .8 meters long.
Color: Gray-brown.
Group size: Singly or in groups of 2-6.
Diet: Squid, octopus, shrimp, small schooling fish.
Description: Harbor porpoises are shy, generally solitary
animals that are rare in southern Puget Sound, but occasionally
sighted in the San Juan Islands. They rarely porpoise like
their relatives the Dall's porpoises, and avoid boat traffic
at all costs. Harbor porpoises inhabit the coastal regions
of the North Pacific and the North Atlantic. A female reaches
sexual maturity at 4 years of age, goes through an 11 month
gestation period, and calves in the late spring or early summer.
The lifespan of a harbor porpoise is fairly short for a cetacean,
averaging between 15 and 20 years.
Compare the dorsal fin to that of a Dall's porpoise.
1b. Dolphins (Family
Delphinidae)
-Orca (Orcinus orca)
orcynus=tunny(tuna) orca="a kind of whale"
Size: Up to 9 meters.
Color: Black and white.
Group size: 1-30 individuals.
Diet: Seals, sea lions, birds, fish.
Description: Orcas found in Northwest waters are divided into
three different races: transients, offshores,and residents.
The transients roam up and down the East Pacific Coast in
search of their favorite food, other marine mammals. Most
of their diet consists of harbor seals, harbor porpoises,
Dall's porpoises, California sea lions, and stellar sea lions.
But they have also been known to eat marine birds, deer and
moose! While foraging, the transients are very quiet, using
no echolocation clicks or communication vocalizations, as
not to alert their prey to their presence. Once their prey
is located and cornered, the orcas will use their fluke to
strike and stun their potential meal, then drown and eat it.
They will join with other transients while hunting, but are
often solitary (especially the adult males, or bulls) or seen
in very small groups (2-3). Transients typically dive for
5 to 15 minutes.
The offshore race was recently discovered (1991) and as a
result, little is known about them. We do know that they travel
in large groups (30-60 individuals), and are rare in inland
waters, typically staying 10-20 kilometers offshore. Their
diet probably consists of fish, as it's advantageous to be
in large groups if you need to capture fish, and because of
the fact that they are very vocal, unlike the transients.
The third race of orcas, the residents, live in very stable
groups and are very vocal. They feed primarily (95%) on salmon,
and other fishes. Researchers have placed these cetaceans
into groups based on similarity of vocalizations, or dialects.
The basic unit the orcas are placed in is called the matrilineal
group, and consists of a female and her male and female offspring.
These groups typically consist of 3-4 generations of up to
9 individuals. Matrilineal groups that are found together
most of the time and that share a common vocal dialect are
put into the next larger social unit called a subpod. Subpods
consist of 1-11 matrilineal groups. If subpods travel often
with other subpods, and can be linked by dialect to these
other subpods, then they are called a pod. Pods are made up
of 1-5 subpods. A clan is the next unit of social organization
for resident orcas and is made up of pods with similar dialects,
that will occasionally travel together. The resident orcas
are further grouped into the largest social unit, the community.
Each clan within the community has its own distinct dialect,
but it has distant relations to the dialects of the other
clans. Whales within a community never travel with whales
of another community. We have two communities in local waters,
the northern community, made up of 3 clans, 16 pods, and 209
individuals, and the southern community, consisting of 1 clan,
3 pods, and 98 individuals (1996). Adult male (bull) orcas
bear distinct and obvious anatomical differences to females
and juvenile males. A bull's dorsal fin is much taller and
lineated on the trailing edge. His pectoral flippers are also
much larger and paddle-shaped, and the edges of his fluke
have a downward curve. Juvenile males are difficult to distinguish
from females as their fins are shaped the same, but can be
distinguished by the pattern of the belly patch. Individual
orcas can be identified by injuries to their dorsal fins,
and the unique design of their saddle patches. (Please see
section 6 on individual orca identification.)
- Pacific White-sided Dolphin (Lagenorhynchus obliquidens)
lagenos=bottle rynchus=snout obliquus=slanting dens=teeth
Size: Up to 2.5 meters.
Color: Gray-black.
Group size: Singly or with a mate.
Diet: Squid, small fish.
Description: Pacific white-sided dolphins are very acrobatic,
leaping out of the water, often while bow riding. They travel
in large groups (50-several hundred) when offshore, but usually
only lone strays make it into Puget Sound and usually end
up getting lost and stranding. They are distinguished by their
large, curved dorsal fin with light shading on the trailing
edge. They do not throw a rooster tail spray like the Dall's
porpoise when they are porpoising.
Occasional and rare Odontocetes
-Northern Right Whale Dolphin
-Saddleback Dolphin
-Risso's Dolphin
-Short-finned Pilot Whale
-False Killer Whale
-Archbeak Whale
-Hubb's Beaked Whale
-Goosebeak Whale
-Baird's Beaked Whale
-Pygmy Sperm Whale
2. Mysticetes (Suborder Mysticeti)
Baleen cetaceans with two blowholes. (All mysticetes are true
whales.)
2a. Gray Whale (Family Eschrichtiidae)
- Gray Whale (Eschrichtius robustus)
Eschricht=a zoologist robustus=strong
Size: Up to 14 meters.
Color: Mottled gray.
Group size: Single individuals or mother-calf pairs.
Diet: Bottom dwelling organisms like amphipods, crab larvae
and worms.
Description: The gray whale is easily identified by it lack
of a dorsal fin. In it's place it has a series of 6-12 barnacle
covered knuckles on its back. Its exhalation, or blow, is
low and bushy, and fairly obvious. Gray whales are notorious
for throwing their flukes or arching steeply before a deep
dive to scour the muddy sea floor for their favorite food:
bugs and worms. Gray whales are often sighted near shore all
up and down the East Pacific Coast as they complete the longest
migration of any of the cetaceans. They spend their winters
in Baja California mating and calving, then in the spring
leave for their 11,200Km (7000 mile) journey to their primary
feeding grounds in the Bering, Chukchi, and Beaufort Seas
in Alaska. After gorging themselves for a few months, they
work their way back down the coast to Baja in the fall. Because
of their unique feeding habits (bottom feeding in shallow
water), and the time elapsed since their last meal (about
six months) the northerly spring migration is a great opportunity
to encounter these whales within view of land-based observers,
as they snack on amphipods and crustaceans in shallow coastal
waters. Gray whales occasionally make their way into Puget
Sound and can travel as far south as Olympia.
Some gray whales have developed an affinity for human interactions
and have been dubbed "friendly's", sometimes spending
hours next to a boat hoping to be petted. Some fear that the
renewed harvesting of gray whales by the Makah tribe (scheduled
for the spring 1996 northerly migration) will destroy this
new kinship between whales and humans (not to speak of the
individual friendly's).
2b. Fin Whales (Family Balaenopteridae)
-Minke Whale (Balaenoptera acutorostrata)
balaena=whale pteron=wing acutus=pointed rostrum=snout
Size: Up to 9.2 meters in Northern Hemisphere.
Color: Black to dark gray dorsal surface, white ventrally.
Group size: 1-3 individuals.
Diet: Small schooling fish and krill.
Description: Minke whales are very distinctive when sighted,
with their tall, falcate dorsal fin set far back on the body.
Their blow is only visible under ideal lighting conditions,
but is very audible. Minkes will occasionally approach stationary
boats for a quick glance, then swim off. If this happens to
you, try to notice the v-shaped head with a narrow ridge just
as it surfaces. Unlike their relative the gray whale, minkes
don't throw their flukes before a deep dive, instead, they
arch their back steeply. Twenty eight individual minkes have
been identified by researchers in our inland waters, and are
regular visitors to the greater Puget Sound region. Minke
whales are the most commonly sighted baleen whales in the
inland waters of Washington, and are the most numerous of
the mysticetes in the world. The reason for this abundance
is their size. At a length of around 9 meters, the minkes
are the smallest of the baleen whales. Historically, whalers
hunted the larger baleen whales because they offered a higher
economic yield. Species formerly hunted in northwest waters
included the humpback, fin, sperm, sei, and blue whales. But
overhunting resulted in a collapse of the stocks of large
whales to the point that it was no longer economically feasible
to hunt them (economic extinction). This left us with only
the smallest of the whales in large numbers. Then, in the
1970's, the whalers began to hunt the only numerous mysticete
left. By the mid-1980's an average of 10,000 minkes were taken
annually by Japan, Norway, Korea, and Taiwan, and the harvest
continues to date. The minkes will also decline to economic
extinction if this continues.
Occasional and rare Mysticetes
-Humpback Whale
-Sei Whale
-Northern Right Whale (fewer than 200 in the world)
Carnivores (Order Carnivora)
3. Pinnipeds (Suborder Pinnipedia)
The seals, sea lions, and walruses.
3a. True Seals (Family Phocidae)
- Harbor Seal (Phoca vitulina)
phoce=seal vitula=calf inus=like
Size: Up to 1.9 meters.
Color: Typically gray with black and white spots. (Can be
tan to black.)
Group size: 1-30 individuals.
Diet: Herring, hake, sculpin, tomcod. (Very little, if any,
predation on salmon.)
Description: The harbor seal is easily distinguished from
the other pinnipeds in Puget Sound by its small size, its
spotted appearance, and its lack of external ear flaps. When
hauled out on shore, the harbor seal's locomotion is also
rather unique, consisting of bouncing and wiggling. It cannot
"walk" like the other common pinnipeds in our area
because its pelvis is fused, instead of hinged, like the California
sea lion's. And, the harbor seal is lacking in any real vocal
repertoire, reduced to quiet cooing between a female and her
newborn pup, which sounds coincidentally like a nasal "maaaaa".
There are about 5000 harbor seals who make Puget Sound their
permanent residence, but the east Pacific species on the whole
ranges from Baja California to the Bering Sea in Alaska. Harbor
seals have a lifespan of about 30 years, with the females
living longer than the males. Gender can be distinguished
only on close inspection of the ventral surface, males having
a genital opening halfway from the naval to the rear flippers,
and females having two nipples a fourth of the way from the
naval to the rear flippers. Harbor seals are often sighted
spyhopping in the water, peeking their head up to look around.
Occasionally they will approach a stationary vessel for a
closer look. If a seal decides to "check you out",
remember that it's a wild animal with sharp teeth, not a cute
cuddly pet who wants to be petted (personal observation).
Harbor seals can also be seen hauling out on a rock, log,
or beach to rest, give birth, or nurse their young. They should
not be approached when participating in this activity, as
mother and newborn can become separated if frightened-off
of the haul-out. This can lead to infant mortality.
Sometimes, a female will leave her pup on shore while she
goes off to fish to replenish her milk supplies. Unknowing
passerby's who try to "rescue" the pup will only
be leading to its demise. Its best to just leave the apparently
abandoned pup alone, as its mother will eventually return
to reclaim it. Predators on the harbor seal include the white
shark, orcas, stellar sea lions, polar bears, coyotes, and
bald eagles.
Three harbor seals have been individually photo-identified
near Bainbridge Island (please see section 7 on individual
harbor seal identification).
3b. Sea Lions (Family
Otariidae)
- II a. California Sea Lion (Zalophus californianus)
za=intensive prefix lophus=crest califronianus=California
Size: Males-2.4meters, 390 Kg. Females-2 meters, 110 Kg.
Color: Dark brown to black.
Group size: 1-10 individuals (non-breeding areas like Puget
Sound).
Diet: Hake, herring. (Also an opportunistic predator that
preys on human concentrated steelhead (not salmon) at the
Ballard Locks.)
Description: The California sea lion is distinguished by its
dark color, long, hairless flippers, and pronounced sagittal
crest (hump) on the adult males forehead. A loud, persistent
bark is the vocal signature this pinniped, and can be heard
for kilometers on a still day. California sea lions are late
fall, winter, and early spring residents of Puget Sound, spending
their summers in rookeries (breeding colonies) in their namesake
state.
California sea lions are generally sighted on haul-outs like
marker buoys or docks, but are occasionally seen free swimming.
They can attain speeds of up to 32 Km/hr (20 mph) and will
sometimes porpoise clear of the water when swimming fast.
Predators include the white shark and transient orcas.
California sea lions are often captured for use in cirsuses,
being improperly labelled as "seals".
- Stellar (Northern) Sea Lion (Eumetopias jubatus)
eu=typical metopion=broad forehead jubatus=having a mane
Size: Male-3.25 meters, 1120 Kg. Female-2.9 meters, 350Kg.
Color: Tan to golden.
Group size: 1-10 individuals (non-breeding areas like Puget
Sound).
Diet: Flounder, cod, rockfish, squid, octopus, salmon, other
pinniped pups.
Description: Stellar sea lions can be distinguished from California
sea lions by their lighter coloration, larger size, much less
pronounced sagittal crest, and thicker neck. Vocalizations
are rarer and consist of a deep roar instead of a sharp bark.
Their breeding range is from California to Alaska, with an
unexplainable lack of rookeries on the Washington coast, and
most of the individuals breeding in Alaska. The number of
the Alaskan Stellar sea lions is dramatically decreasing though,
most likely due to competition for prey with the Alaskan fisheries,
who have caused the collapse of several species of fish from
over-harvesting. Threatened or endangered listing has been
recommended by biologists, but recent legislation has halted
any new listings. Predators include the white shark and transient
orcas.
Occasional and rare Pinnipeds
-Northern Elephant Seal
-Northern Fur Seal
4. Mustelids (Family Mustelidae)
The otters, weasels, and minks.
4a. Otters (Family Mustelidae)
- Sea Otter (Enhydra lutris)
enhydris=Greek for otter lutra=Latin for otter
Size: 1.5 meters, 45 Kg.
Color: Brown with a light gray head.
Group size: Lone individual if sighted in inland waters (very
rare).
Diet: Clams, mussels, abalone, sea urchins, crabs, limpets,
chitons, sea cucumbers, scallops, worms, red octopuses, anemones,
worms.
Description: Sea otters were common on Washington's outer
coast until their extinction from overharvest in the 1800's.
Then, from 1965-1972, about 100 sea otters were successfully
re-introduced on the west coast and are thriving to date,
with current numbers up around 200. These otters rarely make
it into inland waters, though, and most "sea otter"
sightings are actually of river otters.
Sea otters are the largest members of the mustelid family.
They use air trapped in their extremely dense hair to maintain
their buoyancy, and are the most buoyant of all marine mammals.
Sea otters have developed the use of tools, using rocks placed
on their chests to crack-open hard to get at shellfish. Sea
otters also hunt for red octopuses in aluminum cans. They
have discovered that these tiny octopuses will take-up residence
in abandoned cans and will collect cans and tear them open
with their teeth in hopes of finding a succulent meal inside.
- River Otter (Lutra canadensis)
lutra=otter canadensis=Canada
Size: Up to 1.3 meters, 16 Kg.
Color: Brown.
Group size: 1-7 individuals. (Groups are family units.)
Diet: Gunnels, flounder, red rock crabs, red octopuses, surf
perch, sculpins, sea birds and their young.
Description: River otters are often sighted in the inland
waters of Washington state, swimming along on their tummies,
or running along the shore line. They are often confused with
their relatives the sea otters, but are actually quite easily
distinguished from them. River otters swim on their stomachs,
are smaller, have a brown face, and a long, slender tail.
Sea otters swim on their backs, are larger, have a light gray
face, and a short, stocky tail.
River otters are more social than any other of the mustelids,
forming social groups of adult females and her offspring,
and also forming bachelor groups.
River otters are not technically marine mammals and are therefore
not allowed the protection of the Marine Mammal Protection
Act. As a result, about 500 are taken each year from Washington
and Canadian waters for their fur.
Copyright © 1995 Raven Science
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